private bool HandleDragEnd(Func <IInputElement, Point> eventPointExtractor)
{
AnnotationGridVM agVM = DataContext as AnnotationGridVM;
if (agVM != null)
{
if (agVM.DraggedItem != null)
{
Point localOffset = agVM.LocalDraggedItemOffset;
Point curLocation = eventPointExtractor(ColumnsGrid);
Point droppedLocation = new Point(
curLocation.X - localOffset.X + agVM.DraggedItem.ActualWidth / 2, //X coord is the location of the centre of the dragged element
curLocation.Y - localOffset.Y); //Y coord is a top of the dragged element
if (isMouseCaptured)
{
//ReleaseMouseCapture();
System.Diagnostics.Trace.WriteLine("Mouse release");
isMouseCaptured = false;
}
int col = -1;
var htResult = VisualTreeHelper.HitTest(ColumnsGrid, droppedLocation);
if (htResult != null)
{
foreach (UIElement elem in ColumnsGrid.Children)
{
if (IsInVisualTree(htResult.VisualHit, elem))
{
col = Grid.GetColumn(elem);
}
}
}
ElementDropped?.Invoke(this, new ElemDroppedEventArgs(agVM.DraggedItem, col, droppedLocation.Y));
agVM.DraggedItem = null;
return(true);
}
}
return(false);
}
protected override void OnManipulationCompleted(ManipulationCompletedEventArgs e)
{
base.OnManipulationCompleted(e);
ElementDropped?.Invoke(this, new DraggableElementEventArgs(this, DragParent.PointToScreen(e.ManipulationOrigin)));
}